四川盆地混元气藏形成的地质基础  

GEOLOGIC CONDITIONS AND RESERVOIRING PATTERNS OF MIXED-SOURCE GAS POOLS IN SICHUAN BASIN

作　　者：程付启[1] 金强[1] 

机构地区：[1]中国石油大学

出　　处：《天然气工业》2006年第4期11-13,共3页Natural Gas Industry

基　　金：国家重点基础研究发展规划项目(2001CB209102)资助

摘　　要：分析混元气成藏的地质基础、建立混元气成藏的一般模式是混元气定量研究的基础,具有重要的理论和现实意义。勘探开发实践证实四川盆地普遍存2种类型的混元气藏,即不同来源天然气混合形成的混源气藏和同源不同阶天然气混合形成的混合气藏。文章根据盆地演化特征和成藏因素分析,并结合实例,概括出了该盆地混元气藏形成的地质基础和成藏模式。受多旋回构造运动和沉积环境变化的影响,该盆地普遍发育多套类型和成熟度不同的气源岩、多层系近源储集层,以及沟通不同储层的断层与裂缝,这些有利的成藏因素加上复杂的成藏过程构成了混元气藏形成的地质基础。混元气藏的形成模式可以概括为异源原生型、后期调整型和多期充注型3种。其中异源原生型又可分为上移新储型和下移古储型2种。Analysis of geologic conditions of mixed-source gas pools and establishment of their general reservoiring pattern constitute the basis of quantitative study, thus are of important theoretical and practical significances. Two types of mixed-source gas pool are common in Sichuan Basin, one containing mixed gas generated by different source rocks and the other containing mixed gas generated by the same source rocks at different thermal maturity stages. The geologic conditions and reservoiring patterns of mixed-source gas pools in Sichuan Basin are studied based on analysis of the characteristics of basin evolution and reservoiring factors and in combination with case study. Several gas source rock intervals of different types and in different maturities, multiple reservoirs near source rocks and faults and fractures linking up different reservoirs are commonly developed in this basin, due to the influences of multicyclic tectonic movements and change of sedimentary environments. These favorable reservoiring factors in combination with complex reservoiring process constitute the geologic conditions of mix-sourced gas reservoirs. Their reservoiring patterns can be classified into hetero-source primary type, late-reformation type, and polyphase charging type, of which the hetero-source primary gas pools can be further divided into two subtypes, i.e. migrating upward-accumulating in younger reservoir and migrating downward-accumulating in older reservoir.

关 键 词：混元气藏 地质基础 成藏形成 模式 四川盆地 

分 类 号：P618.13[天文地球—矿床学]